Leaders of the world's largest economies complete their summit in St. Petersburg, Russia today.

NPR's Corey Flintoff reports this meeting has been marked by a growing divide between the most highly developed nations and emerging economies.

COREY FLINTOFF, BYLINE: When times were toughest during the worldwide recession, the world's top 20 economic powers were able to act with remarkable unity. Now that the United States and other developed nations are seeing modest signs of improvement, though, it's getting harder to agree on key issues.

Because the U.S. economy is improving, the Federal Reserve is looking to cut back on a stimulus program that has been pumping $85 billion a month into the world economy. That program made it possible for investors to borrow dollars at low interest rates and invest them in places that were experiencing rapid growth despite the recession.

CHRIS WEAFER: And there's been a very big flow of capital from the U.S. and from Europe into Asia and other emerging markets since 2009, and of course, that's helped then bolster the economies of those countries.

India and Indonesia were among the big beneficiaries of that investment, as well as Brazil. But with the economy improving in the United States and the flow of cheap dollars gradually drying up, investors will be tempted to pull money out of those riskier countries and reinvest it in the developed world.

Federal Reserve chairman Ben Bernanke indicated back in May that the Fed might start tapering off the amount of money it was pushing into the economy. Weafer says the chairman's vague comments created uncertainty among investors.

WEAFER: And because of the mixed signals that that kind of given, when how and when we will do it, we've seen almost a panic move of investors out of emerging markets.

FLINTOFF: The mere hint that the U.S. might reduce the flow of cheap dollars triggered a 20 percent collapse in the value of the Indian rupee. Currencies in Indonesia and Brazil were also hard hit, driving up local prices and slowing their economies. Even China's booming growth took a hit, as credit dried up and spending slowed.

Russian President Vladimir Putin summed the problem up in his speech to the other G-20 leaders.

PRESIDENT VLADIMIR PUTIN: (Foreign language spoken)

FLINTOFF: Our main task, he said, is returning the global economy toward steady and balanced growth. This task has unfortunately, not been resolved.

Leaders of the emerging countries want the Federal Reserve to be clear about when and how it plans to taper off the amount of money it's pumping into the economy. They say the biggest danger is investor uncertainty. But the American delegation signaled that the emerging economies shouldn't count on the Fed to accommodate them.

Obama adviser Ben Rhodes stressed that the United States has been pursuing a pro-growth policy that ultimately helps economies around the world. He hinted that countries that have relied heavily on exports need to build up their own domestic consumer markets.

BEN RHODES: That's part of the re-balancing of global growth that we've discussed for four and a half years now. So that there are steps that can be taken, so that merging economies can, again, find growth not just from consumers in the United States, but from within their borders.

FLINTOFF: There are signs that the emerging economies plan to help themselves and each other. The so-called BRICS countries - Brazil, Russia, India, China and South Africa - announced plans to create a $100 billion currency reserve pool that could provide a cushion in any future crisis.

It's not clear when the Federal Reserve will actually start to turn off the money tap, but many analysts believe that it could start happening later this month.